降低适用于高密记录写入磁头的Fe-N薄膜矫顽力的研究

Seeking Ways to Reduce the Coercivity of Fe-N Soft Magnetic Films

用RF磁控溅射方法,在高功率下制备厚度为2μm的薄膜,当N含量在5.9～8.5%原子分数范围内,形成α′+α″相时,4πMs=2.2T,Hc=58.6A/m,可以满足针对高存储密度的GMR/感应式复合读写磁头中写入磁头的需要。用该方法在不同的本底真空度下制备Fe N薄膜,发现较高真空下比较低真空下制备的Fe N薄膜磁学性能要好。P=1000W时,较高真空下制备的Fe N薄膜的矫顽力为34.8A/m,较低真空下制备的Fe N薄膜的矫顽力为58.6A/m。AFM测试表明,在功率条件相同情况下,较高真空下制备的Fe N薄膜表面光滑、平整、起伏小、薄膜致密;而较低真空下制备的Fe N薄膜,表面粗糙、起伏大、薄膜较疏松、不均匀。

Fe-N films 2μm thick keep their excellent magnetic properties of 4πMs=2.2T, Hc<80A/m when the nitrogen content is in the range of 5.9-8.5 at.%. These films meet the requirements of recording heads.Fe-N thin films were fabricated at different base pressure. It is found that the magnetic properties of those prepared in high vacuum are much better than those of films prepared in low vacuum. The coercivity of the former is 34.8A/m. The structural analysis showed that there are few defects and weak stress in the Fe-N films prepared in high vacuum, but many defects and strong stress in those prepared in low vacuum.